Since electric energy came into commercial use as power systems, the engineers have made many efforts to model the performance of system equipment and simulate power system phenomena to avoid unexpected problems. Fuji Electric as an equipment manufacturer and power control system engineering company has pushed research and development for various simulation technique and software toward establishing power system analysis technology. This paper focuses on Fuji Electric's recent development of computer simulation tools and hybrid simulators for power system analysis.

This paper describes the specification of the userfriendly man-machine interface of the Electromagnetic transients program (EMTP), citing two developed examples: (1) the versatile interface and managing system on EWS (2) the simplified lightning surge analysis system on personal computers. The advantages of these systems are to assist in setting conditions and parameters on the graphic interface, to create and manage input-output data files automatically, and to help in documentation for assessing and assembling the results. Untroubled by time-consuming jobs, the user can concentrate on assessing simulation results.

With the recent progress in power electronics, large capacity self-commutated inverter systems have come into use in electric power system. The control systems for the wide-ranging uses are required to have advanced functions and high performance. This paper describes the computer simulations applied to the development of large capacity self-commutated inverters, such as self-commutated inverters for flicker compensation, large capacity system interconnecting inverters, and self-commutated inverters for reactive power compensation.

This paper presents the trend of three-phase unbalanced load flow analysis technology and the unbalanced load flow analysis program developed by Fuji Electric. The program utilizes phase presentation and selects an appropriate algorithm for high and low voltage power systems. Written with standard C language and modularized, it can be called easily as a basic power system calculation package from various functions. The execution time for a practical 394 bus system is approximately 2.5 seconds on Fujitsu S4/10.

Against complicated phenomena in power systems, to improve system analysis technology and verify the operation of new protective and control systems with exact models, power system simulators have been introduced. Fuji Electric jointly with The Tokyo Electric Power Co. has developed a hybrid power system simulator analog part improved in the function of equipment models and the ease of operation and maintenance of the analysis system and delivered it to TEPCO R&D CENTERS. This paper introduces the target specification of the simulator, an outline of the whole equipment, and examples of analyses.

Analog simulators capable of real-time operation have been put to practical use as a means of analyzing various phenomena in power systems. With its experiences in the large-scale simulators delivered to The Kansai Electric Power and Chubu Electric Power Cos., Fuji Electric has supplied analog models for 11 generators, 65 transmission lines, etc., to TEPCO R&D CENTERS of the Tokyo Electric Power Co., Inc. This paper outlines the various equipment models such as generators, transmission lines, and transformers, in this new simulator.

A power system simulator is an effective means of improving system analysis technology and verifying system quality. The characteristic operation of analog simulators in preparatory work such as connection for the main and measuring circuits, setting constants to the equipment models, and setting up the test circuits, and a supporting function is indispensable for this work. Fuji Electric has supplied a new operation supporting system for the advanced analog simulator to TEPCO R&D CENTERS of The Tokyo Electric Power Co., which is introduced in this paper.

Hydrogenated amorphous silicon germanium (a-SiGe:H) has been prepared by RF plasma CVD. Electron temperature in the plasma decreases and photosensitivity (σph/σd) of the a-SiGe:H film increases by about 2 times as an electrode gap increases while keeping substrate temperature constant. A high quality a-SiGe:H film of σph/σd = 3 × 10⁵ at the optical gap of 1.6eV is obtained through optimization of films. The "ion energy controlled plasma CVD" developed in the study allows to control incident ion energy (Vs) onto substrates independently of surrounding plasma. Spin density of hydrogenated amorphous silicon increases as Vs increases.

Fuji Electric has been making a basic study of thin film devices based on organic materials because of their potential for future optelectronic devices. Quasi-one-dimensional hetero-structures are synthesized by introducing a barrier into the oligothiophene backbone. By changing the oilgothiophene length and the barrier structure, conjugation length and optical properties can be controlled. Moreover, molecular orientation in thin films also can be controlled by changing the oligomer backbone structure, i.e. barrier structure.

The guard-ring structure as an edge termination for high-voltage SiC Schottky barrier diodes is proposed. The local oxidation process is used to form the mesa of a p-n junction as the guard ring. The comparison between Al/Ti Schottky barrier diodes with and without the guard-ring indicates the effectiveness of the guard-ring to relax the electric field. The result shows the breakdown voltage is about two times higher with a high yield rate.

Because of recent reduction in price, personal computers have rapidly come into wide use not only for households but also for workshops. System construction incorporating personal computers is becoming the mainstream in place of general-purpose computers and workstations.
This paper describes an example of a factory automation system introduced into the production process of synthetic fiber for the material of zipper tapes (margins to sew up).